Direct role for the Drosophila GIGYF protein in 4EHP-mediated mRNA repression.

摘要: The eIF4E-homologous protein (4EHP) is a translational repressor that competes with eIF4E for binding to the 5'-cap structure of specific mRNAs, which it recruited by factors such as GRB10-interacting GYF (glycine-tyrosine-phenylalanine domain) proteins (GIGYF). Several experimental evidences suggest GIGYF are not merely facilitating 4EHP recruitment transcripts but actually required activity complex. However, underlying molecular mechanism unknown. Here, we investigated role uncharacterized Drosophila melanogaster (Dm) in post-transcriptional mRNA regulation. We show that, when complex 4EHP, Dm only elicits repression also promotes target decay via additional effector proteins. identified RNA helicase Me31B/DDX6, decapping activator HPat and CCR4-NOT deadenylase partners Recruitment Me31B discrete motifs conserved among metazoan downregulation expression 4EHP-GIGYF Our findings consistent model additionally recruit deadenylation complexes 4EHP-containing RNPs induce degradation targets.